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Strain-tuned enhancement of ferromagnetic T_C to 176?K in Sm-doped BiMnO₃ thin films and determination of magnetic phase diagram.

ABSTRACT: BiMnO₃ is a promising multiferroic material but it's ferromagnetic T_C is well below room temperature and the magnetic phase diagram is unknown. In this work, the relationship between magnetic transition temperature (T_C) and the substrate induced (pseudo-) tetragonal distortion (ratio of out-of-plane to in-plane lattice parameters, c/a) in BiMnO₃ thin films, lightly doped to optimize lattice dimensions, was determined. For c/a?>?0.99, hidden antiferromagnetism was revealed and the magnetisation versus temperature curves showed a tail behaviour, whereas for c/a?C of up to 176?K, more than 70?K higher than for bulk BiMnO₃, was achieved through precise strain tuning. The T_C was maximised for strong tensile in-plane strain which produced weak octahedral rotations in the out-of-plane direction, an orthorhombic-like structure, and strong ferromagnetic coupling.

SUBMITTER: Choi EM

PROVIDER: S-EPMC5335565 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Strain-tuned enhancement of ferromagnetic TC to 176 K in Sm-doped BiMnO3 thin films and determination of magnetic phase diagram.

Choi Eun-Mi EM Kleibeuker Josée E JE MacManus-Driscoll Judith L JL

Scientific reports 20170303

BiMnO3 is a promising multiferroic material but it's ferromagnetic TC is well below room temperature and the magnetic phase diagram is unknown. In this work, the relationship between magnetic transition temperature (TC) and the substrate induced (pseudo-) tetragonal distortion (ratio of out-of-plane to in-plane lattice parameters, c/a) in BiMnO3 thin films, lightly doped to optimize lattice dimensions, was determined. For c/a > 0.99, hidden antiferroma ...[more]

PMID: 28256606

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